The best way to travel around the Japanese alps is to hire a car in Tokyo itself or at the airport. Rates are reasonable, the roads are well signposted in English, and fuel is cheaper than in Britain. However the expressway tolls are quite expensive. I would recommend Toyota Rental Lease (rent.toyota.co.jp/top.asp - only in Japanese, unfortunately), which has a network of 1,100 branches across the country. One of the best places to see monkeys has to be Jigokudani ('Hell Valley') in northern Nagano, where they come to bathe in sulphorous springs, and you can challenge yourself to do the same (see outdoorjapan.com /TO/0311/ TO-3-jigokudani.html). There should be plenty of time to take in Takayama, which is delightful, as well if you're driving, and the route from northern Nagano across to Gifu will afford spectacular views.
Richard Hendy